Low-chlorine, polyolefin-substituted, with amine reacted, alpha-beta unsaturated carboxylic compounds

ABSTRACT

A composition of matter comprising an amine acylated with a hydrocarbyl group substituted carboxylic acylating agent containing an average of from 1.3 to 1.6 groups derived from α,β-unsaturated carboxylic compounds per  M   n  of the hydrocarbyl group, wherein the hydrocarbyl group has  M   n  determined by GPC ranging from 1500 to 3000, the amine comprises polyamine bottoms and said acylated amine has total base number (TBN) ranging from 17 to 35. A method for preparing the composition, lubricating oils containing the composition and, in another embodiment, lubricating oil compositions of this invention further comprising a metal overbased sulfonate detergent.

FIELD OF THE INVENTION

The present invention relates to high performance dispersants forlubricating oil compositions, particularly ashless dispersants, moreparticularly succinimide dispersants, for engine lubricating oils.

BACKGROUND OF THE INVENTION

The ILSAC (International Lubricant Standardization and ApprovalCommittee) GF-3 Minimum Performance Standard for Passenger Car EngineOils, published Oct. 12, 2000 is a cooperative standard from majorautomobile manufacturers throughout the world and the EngineManufacturers Association, Inc. This standard specifies the minimumperformance requirements (both engine sequence and bench tests) andchemical and physical properties for those engine oils thatmanufacturers deem necessary for satisfactory equipment performance andlife.

Problems with the current situation for the synthesis of lubricantadditives outlined above is that they have a high halogen content whichis causing increased environmental concerns for the continued use of thelubricants and fuels containing them. Low chlorine or chlorine freelubricants are becoming more and more desirable.

A heretofore preferred manner of making lubricant additives has been toalkylate α-β unsaturated acids or anhydrides in the presence of chlorinethen to convert the resulting acylating agent to a derivative such as anester, amide, imide, or metal salt. This type of reaction yields halogencontaining polyalkenyl or hydrocarbyl-substituted acids or anhydrideswhich may be called alkyl substituted carboxylic acylating agents. Thesubstituted carboxylic acylating agents containing halogen can then befurther reacted with amines, polyamines, alcohols, amino-alcohols ormetal salts to form halogen containing dispersants, esters and metalsalts. It is not uncommon for the polyalkenyl-substituted carboxylicacylating agents to have chlorine contents of 0.5-1%. This correspondsto 5,000-10,000 parts per million chlorine.

Examples of U.S. patents which describe methods for preparinghydrocarbyl-substituted aliphatic carboxylic acylating agents, andparticularly polyalkenyl-substituted carboxylic acylating agentsutilizing various amounts of chlorine include U.S. Pat. No. 3,215,707(Rense); U.S. Pat. No. 3,231,587 (Rense); U.S. Pat. No. 3,454,607(LeSuer); U.S. Pat. Nos. 3,912,764; 4,110,349; 4,234,435 (Meinhardt);and U.S. Pat. No. 5,041,622 (LeSuer). U.S. Pat. No. 4,234,435 describescarboxylic derivative compositions produced by reacting at least onesubstituted succinic acylating agent with a reactant such as amines,alcohols, reactive metals or combinations thereof. The substitutedsuccinic acylating agent consists of polyalkenyl substituent groups andsuccinic groups. The substituent groups are derived from a polyalkenehaving an M _(n) value of about 1300 to about 5000 and an M _(w)/ M _(n)value of about 1.5 to about 4. The acylating agents are characterized bythe presence within their structure of an average of more than onesuccinic group for each equivalent weight of substituent groups. Becauseof the presence of the excess of succinic groups in the acylatingagents, such compounds have been referred to in the art as “oversuccinated,” and the products described in the '435 patent have alsobeen characterized as detergents and viscosity improving additives inlubricating oil compositions. When such derivatives are incorporatedinto lubricating compositions, they impart sufficient fluidity modifyingproperties to the lubricant which are sufficient to permit eliminationof all or a significant amount of viscosity index improver frommulti-grade lubricant compositions.

The acylating agents utilized in preparing the lubricant additivesdescribed in U.S. Pat. No. 4,234,435 are prepared by reaction ofpolyisobutene polymer with an α-β unsaturated dicarboxylic acid oranhydride such as maleic anhydride in the presence of chlorine. In suchinstances, the products which are obtained from the reaction and theproducts obtained from subsequent reaction with amines, alcohols,alcohols and metal compounds contain various amounts of halogen. Due toenvironmental concerns, it has now become desirable to eliminate orreduce the level of chlorine. One potential solution to eliminating thechlorine contained in such lubricant and fuel additives is simply to notuse chlorine in the manufacturing process. Another potential solution isto develop procedures for treating such compositions to remove thechlorine which is present.

One procedure for treating various chlorine-containing organic compoundsto reduce the level of chlorine therein has been described in a Europeanpatent application published under Publication No. 684 262. Theprocedure comprises heating, particularly under a nitrogen purge,chlorine containing succinic compounds. U.S. Pat. No. 4,282,157discusses a method for preparing lower chlorine containing polyalkenylsubstituted succinic anhydrides and U.S. Pat. No. 4,330,471 relates toalkylene polyamine derivatives of these succinic anhydrides.

Published European patent application No. 655,242 describes a procedurefor reducing the chlorine content of organochlorine compounds comprisingintroducing a source of iodine or bromine into the organochlorinecompound and contacting the components of the resulting mixture for asufficient amount of time to reduce the chlorine content withoutsubstantially incorporating iodine or bromine into the organochlorinecompound. This procedure is successful in reducing the chlorine contentof organochlorine compounds, but in some instances, it is desirable toeven further reduce the amount of chlorine in additive compositionswhich are to be utilized in lubricants and fuels.

Another published method of reducing the chlorine content oforgano-chlorine compounds is described in U.S. Pat. No. 5,489,390. Themethod comprises treating the chlorine-containing compound with an acid.

As mentioned above, one technique for reducing the amount of chlorine inadditive compositions based on polyalkenyl-substituted dicarboxylicacids is to prepare such hydrocarbon-substituted dicarboxylic acids inthe absence of chlorine, and procedures have been described forpreparing such compounds by the “thermal” process in which thepolyolefin and the unsaturated dicarboxylic acid are heated together,optionally in the presence of a catalyst.

U.S. Pat. No. 6,077,909 relates to a method for producing polyolefinsubstituted carboxylic acylating agents having less than 1000 ppmchlorine and reaction products, such as dispersants, formed therefrom.

U.S. Pat. No. 6,165,235 describes polyolefin substituted carboxylicacylating agents having chlorine content <2000 ppm and having a degreeof succination ranging from 1.1-2, said acylating agents being furtherreacted with amines and/or alcohols to form dispersants having reducedchlorine content.

U.S. Pat. Nos. 4,904,401; 4,938,881; 4,952,328; 4,957,649 and 4,981,602relate to lubricating oil compositions, particularly to lubricating oilcompositions meeting certain industry specifications.

It has now been found that nitrogen-containing carboxylic dispersantshaving hydrocarbyl substituent groups having a specified minimum numberaverage molecular weight ( M _(n)), derived from hydrocarbyl substitutedacylating agents having a specified minimum degree of succination,having a specified total base number and derived from certain aminereactants, provide lubricants meeting GF-3 and top-tier Europeanlubricant requirements, offer good economics and allow for formulationof low chlorine containing products.

Requirements for top tier lubricants include improved seals performanceas measured by the VW Seals test (PV3344), a fluoroelastomer stabilitytest, piston deposits and ring sticking better than a standard, baselinelubricant using the Volkswagen 1.6L Diesel Intercooler test (VolkswagenVW TDI test), and improved extended drain capability as measured by theVolkswagen T4 test (Test method PV 1449)

SUMMARY OF THE INVENTION

The present invention relates to a composition of matter comprising anamine acylated with a hydrocarbyl group substituted carboxylic acylatingagent containing an average of 1.3 to 1.6 groups derived fromα,β-unsaturated carboxylic compounds per M _(n) of the hydrocarbylgroup, that is, per equivalent of the hydrocarbyl group, defined as M_(n), determined by GPC, which is 1500 to 3000, the amine comprisespolyamine bottoms and said acylated amine has total base number (TBN) of17 to 35 on a neat chemical basis.

The invention further provides a method for preparing the abovecomposition, lubricating oils containing the composition and, in anotherembodiment, lubricating oil compositions of this invention furthercomprising a metal overbased sulfonate detergent.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term “hydrocarbon” means a group which is purelyhydrocarbon, that is, a compound of hydrogen and carbon containing nohetero atoms. The terms “hydrocarbyl” and “hydrocarbon based” means thatthe group being described has predominantly hydrocarbon character withinthe context of this invention. Hydrocarbyl and hydrocarbon based groupsinclude groups that are purely hydrocarbon in nature, that is, theycontain only carbon and hydrogen. They may also include groupscontaining non-hydrocarbon substituents or atoms which do not alter thepredominantly hydrocarbon character of the group. Such substituents mayinclude halo-, alkoxy-, or nitro-. These groups also may contain heteroatoms. Suitable hetero atoms will be apparent to those skilled in theart and include, for example, sulfur, nitrogen and oxygen. Therefore,while remaining predominantly hydrocarbon in character within thecontext of this invention, these groups may contain atoms other thancarbon present in a chain or ring otherwise composed of carbon atoms.Thus, the terms “hydrocarbyl” and “hydrocarbon based” are broader thanthe term “hydrocarbon” since all hydrocarbon groups are also hydrocarbylor “hydrocarbon based” groups while hydrocarbyl groups or hydrocarbonbased groups containing hetero atoms are not hydrocarbon groups asdefined herein.

In general, no more than three non-hydrocarbon substituents or heteroatoms, and preferably no more than one, will be present for every 10carbon atoms in hydrocarbyl or hydrocarbon based groups. Mostpreferably, these groups are purely hydrocarbon in nature, that is theyare essentially free of atoms other than carbon and hydrogen.

Throughout the specification and claims the expression oil soluble ordispersible is used. By oil soluble or dispersible is meant that anamount needed to provide the desired level of activity or performancecan be incorporated by being dissolved, dispersed or suspended in an oilof lubricating viscosity. Usually, this means that at least 0.001% byweight of the material can be incorporated in a lubricating oilcomposition. For a further discussion of the terms oil soluble anddispersible, particularly “stably dispersible”, see U.S. Pat. No.4,320,019 which is expressly incorporated herein by reference forrelevant teachings in this regard.

It must be noted that as used in this specification and appended claims,the singular forms also include the plural unless the context clearlydictates otherwise. Thus the singular forms “a”, “an”, and “the” includethe plural; for example “an olefin” includes mixtures of olefins of thesame type. As another example the singular form “olefin” is intended toinclude both singular and plural unless the context clearly indicatesotherwise.

Hydrocarbyl Substituted Carboxylic Acylating Agent

The compositions of this invention are amines acylated with hydrocarbylgroup substituted carboxylic acylating agent containing an average of1.4 to 1.6 groups derived from α,β-unsaturated carboxylic compounds perequivalent of the hydrocarbyl group, that is, per M _(n) of thehydrocarbyl group, wherein the hydrocarbyl group has M _(n) determinedby GPC of 1500 or 1700 to 3000 and the amine comprises polyamine bottomsand said acylated amine has total base number of 20 to 35 on a neatchemical basis.

Preferably, the hydrocarbyl group substituent is an aliphatic polyolefingroup, wherein the polyolefin is derived from aliphatic olefinscontaining 2 to 30 carbon atoms, preferably 3 to 8 carbon atoms, morepreferably, propylene and butene and especially isobutylene. Preferredpolyolefin groups are polypropylene and polybutenes. Polyisobutylene isparticularly preferred. Preferred polyolefins comprise polyisobutylenewherein at least 5% of the terminal groups are vinylidene groups,preferably at least 30% terminal vinylidene groups.

The hydrocarbyl-substituted carboxylic acylating agents of the presentinvention include carboxylic acids and their reactive equivalents suchas acid halides, anhydrides, and esters, including partial esters. Thesemay be mono or polycarboxylic acid materials or reactive equivalentsthereof. Examples of carboxylic groups are propionic and succinicgroups. Preferably, the hydrocarbyl substituted carboxylic acylatingagents are polycarboxylic acylating agents and especially, succinicacylating agents.

In one preferred embodiment, the hydrocarbyl substituted carboxylicacylating agent comprises at least one hydrocarbyl-substituted succinicacylating agent consisting of at least one hydrocarbyl substituent andat least one succinic group wherein the hydrocarbyl substituent isderived from a polyolefin, preferably, polyisobutylene.

The hydrocarbyl-substituted succinic acid or succinic anhydride can berepresented correspondingly by the formulas

wherein R is a hydrocarbyl group.

The hydrocarbyl substituted carboxylic acylating agents are prepared bythe reaction of one or more of the above-described polyolefins with oneor more unsaturated carboxylic reagents. The unsaturated carboxylicreagents include unsaturated carboxylic acids per se and functionalderivatives thereof, such as anhydrides, esters, salts and acylhalides,. The unsaturated carboxylic reagents include mono-, di-, tri,or tetracarboxylic acids. Examples of useful unsaturated monobasic acidsinclude acrylic acid, methacrylic acid, cinnamic acid, crotonic acid,and 2-phenylpropenoic acid. Polybasic unsaturated carboxylic acidsinclude maleic acid, fumaric acid, mesaconic acid, itaconic acid, andcitraconic acid; their anhydrides are preferred and maleic anhydride isparticularly preferred. Reactive equivalents of such anhydrides includethe above-mentioned derivative, e.g., acids, esters, half esters, salts,and acyl halides, which can also serve as carboxylic reagents.

The acylating agents can be prepared by reacting one or more of thepolyolefins with, typically, a stoichiometric excess of a carboxylicreagent such as maleic anhydride. Such reaction provides a substitutedcarboxylic acylating agent having at least one carboxylic group,preferably succinic groups, For each equivalent weight of thehydrocarbyl group, there may be more than one carboxylic group.

For purposes of this calculation, the number of equivalent weight ofsubstituent groups is deemed to be the number corresponding to thequotient obtained by dividing the M _(n) (number average molecularweight) value of the polyalkene from which the substituent is derivedinto the total weight of the substituent groups present in thesubstituted acylating agent. Thus, if a substituted succinic acylatingagent is characterized by a total weight of substituent group of 40,000and the M _(n) value for the polyalkene from which the substituentgroups are derived is 2000, then that substituted succinic acylatingagent is characterized by a total of 20 (40,000/2000=20) equivalentweights of substituent groups.

Methods for preparing succinic acylating agents satisfying theseparameters are described in U.S. Pat. No. 4,234,435. In particular, thispatent discloses (in column 19) a process for preparing such materialsby heating at a temperature of about 160° C. to about 220° C. a mixturecomprising: Polybutene characterized by a M _(n) value of about 1700 toabout 2400, in which at least 50% of the total units derived frombutenes is derived from isobutene; one or more acidic reactants of theformula

wherein R and R′ are each —OH or when taken together, R and R′ are —O—;and chlorine.

Specific examples of preparation of such acylating agents are set forthin Examples 1 through 9 of U.S. Pat. No. 4,234,435. Similar examples canbe found in U.S. Pat. Nos. 3,215,707, 3,219,666, and 3,231,587.

The hydrocarbon group substituted acylating agent may be prepared by aprocess comprising forming a mixture of a polyolefin having a total oftetra- and tri-substituted unsaturated end groups up to 90 mole % basedon moles of polyolefin and a halogen selected from the group consistingof chlorine and bromine, wherein said halogen is present in said mixtureon a molar basis up to an amount equal to the moles of tetra- andtri-substituted end groups and adding to said mixture of 1.5 to 2.5moles, per equivalent of polyolefin, of an α,β-unsaturated carboxyliccompound, sequentially or simultaneously with addition of said halogen,reacting said mixture at 170° C. to 220° C. to effect reaction of thepolyolefin and α,β-unsaturated carboxylic compound, reducing thetemperature to less than 200° C. and adding thereto additional halogenand α,β-unsaturated carboxylic compound in about equal molar amountsthen reacting the mixture to reduce unreacted α,β-unsaturated carboxyliccompound to less than 3%.

In another embodiment, the hydrocarbon group substituted acylating agentmay be prepared by a process comprising forming a mixture of apolyolefin having a total of tetra- and tri-substituted unsaturated endgroups up to 90 mole % based on moles of polyolefin and a halogenselected from the group consisting of chlorine and bromine, wherein saidhalogen is present in said mixture on a molar basis up to an amountequal to the moles of tetra- and tri-substituted end groups and addingto said mixture 1.5 to 2.5 moles per equivalent of polyolefin of anα,β-unsaturated carboxylic compound, sequentially or simultaneously withaddition of said halogen, reacting said mixture at 170° C. to 220° C. toeffect reaction of the polyolefin and α,β-unsaturated carboxyliccompound, reducing the temperature to less than 200° C. and addingthereto additional halogen on a molar basis up to an amount equal to themoles of tetra- and tri-substituted end groups, then reacting themixture to reduce unreacted. α,β-unsaturated carboxylic compound to lessthan 3%.

Other processes can be used, if desired, which do not employ chlorine,and this is preferred if the presence of chlorine is undesirable forenvironmental reasons. Bromine can be used in place of chlorine; or thereactants can be heated together at 150 to 200 or 230° C. in the absenceof halogen. Moreover, it is generally unnecessary to use chlorine whenusing high vinylidene polyolefin reactants. The hydrocarbyl groupsubstituted acylating agent may be prepared by direct thermal alkylationof an α,β-unsaturated carboxylic compound with a polyolefin. Preparationusing the so-called “thermal” route is generally described in EuropeanPatent 355,895.

In the formation of the hydrocarbyl-substituted acylating agent, theconditions for the reaction of the polyolefin with the carboxylicreagent such as maleic anhydride, and the relative concentrations ofsuch components, should preferably be sufficient that a majority of theolefin polymer has reacted with at least one molecule of the acylatingreagent. That is, it is preferred, for optimum performance that no morethan 30 percent by weight of the polymer should remain unreacted in theresulting acylating agent, preferably no more than 25 percent, and morepreferably no more than 20 percent, should remain unreacted. For thepurposes of this invention, unreacted polyolefin is often considered toconstitute part of the diluent.

While reaction of the polyolefin with the carboxylic reagent ispreferably conducted in the absence of chlorine, it is possible toprepare hydrocarbyl substituted acylating agents by a process involvingchlorine. However, it is especially preferred that the preparation ofthe hydrocarbyl substituted acylating agent be conducted in the absenceof chlorine.

The resulting hydrocarbyl substituted carboxylic acylating agentcontains an average of 1.3 to 1.6 groups derived from α,β-unsaturatedcarboxylic compounds per M _(n) of the hydrocarbyl group; in variousembodiments, 1.3 to 1.4, or 1.4 to 1.6. When the α,β-unsaturatedcarboxylic compound is a dicarboxy compound, such as maleic acid ormaleic anhydride, each such group will comprise two individual carboxymoieties; thus there can be 2.6 to 3.2 individual carboxy moieties per M_(n) of the hydrocarbyl group.

Amine Reactant

The amine reactants useful in this invention are those described in theart as “polyamine bottoms.” Polyamine bottoms are polyamine mixturesobtained as the residue from stripping complex mixtures of alkylene,usually ethylene, polyamines which complex mixtures include cycliccondensation products such as piperazines. These complex alkylenepolyamine mixtures are typically those produced by the reaction ofalkylene chloride, usually alkylene dichlorides, with ammonia orreaction of an ethylene imine with a ring opening reagent such as wateror ammonia.

In general, alkylene polyamine bottoms can be characterized as havingless than 2%, usually less than 1% by weight material boiling below 200°C.

Typical of such ethylene polyamine bottoms is that designated as“E-100,” obtained from Dow Chemical Co., Freeport Tex., USA. Thismaterial has nominal specifications of specific gravity at 15.6° C. of1.0168; % N=33.15, kinematic viscosity at 40° C.=121 mm²/s (centistokes,cSt). Gas chromatography shows it contains about 0.93% light ends (mostprobably diethylene triamine), 0.72% triethylenetetramine,tetraethylenepentamine and 76.61% pentaethylene hexamine and higher (allby weight). Another example of polyethylene bottoms is a product sold byUnion Carbide Chemicals as HPA-X, having equivalent weight (per N)=40.5.

The polyamines contain at least one >N—H group per molecule. Thesepolyamines bottoms can be reacted solely with the acylating agent orthey can be used with other amines, polyamines or mixtures thereof,provided that the major amount, on an equivalent N—H basis, is alkylenepolyamine bottoms.

The acylated amine comprises at least one member of the group consistingof amide, imide and salt. Often the acylated amine is a mixture of twoor more of these.

The acylated amine of this invention typically possesses a base numberarising from the presence of the amine. Often the total base number on aneat chemical basis (that is, correcting for the presence of any diluentoil) is 17 or 20 to 35, more often 20 or 24 to 30. In one embodiment itcan be 17 to 20. When the acylated amine is prepared from a low chlorinecontaining acylating agent the chlorine content of the acylated aminealso is correspondingly low. Typically, the chlorine content, on a neatchemical basis, is up to 0.6% e.g., 0.01% to 0.6% or to 0.4% or to 0.2%.

Reactions to prepare the hydrocarbyl substituted acylating agent areusually conducted in the substantial absence of diluent, although asubstantially inert, normally liquid diluent such as mineral oil orhydrocarbon solvent may be used. The reaction of the hydrocarbylsubstituted acylating agent with the amine may also be conducted neat orin the presence of a substantially inert, normally liquid diluent.Typically, if a diluent is used, it comprises mineral oil which remainsin the product. If volatile diluents are used, it is usually necessaryto remove the diluent by techniques such as distillation such that theresulting product has an acceptable flash point, i.e., is notunacceptably flammable. When a diluent is present in the acylated amine,it is usually present in an amount of 30 to 70 parts per 100 parts ofacylated amine. As noted hereinabove, polyolefin remaining unreactedfrom the reaction forming the hydrocarbon group substituted acylatingagent is deemed to be part of the diluent.

The following examples illustrate hydrocarbyl substituted carboxylicacylating agents and acylated amines of this invention. All temperaturesare in degrees Celsius, parts and percentages are by weight andfiltrations are conducted with a diatomaceous earth filter aid.

EXAMPLE 1

A reactor is charged with 1000 parts of polyisobutylene having M _(n)approximately 2000 and 76 parts maleic anhydride. The materials areheated to 138° C. whereupon 30.2 parts chlorine are added over 5 hourswhile the temperature is increased to 165° C. The batch is then heatedto 182° C. and held for 1 hour. A second chlorination is begun and atotal of 30.2 parts chlorine are added over 5 hours while thetemperature is increased to 196° C. The batch is then held for a minimumof 2 hours until the batch contains unreacted maleic anhydride less than0.90%. The residue contains 0.38% Cl.

EXAMPLE 2

The process of Example 1 is continued, heating at 232° C. and holding attemperature for 4 hours followed by 4 more hours at 216° C. % Cl=0.12.

EXAMPLE 3

A reactor is charged with 1000 parts of the product of Example 1 and780.0 parts mineral oil. After the temperature is adjusted to 110° C.,46.24 parts of polyethyleneamine bottoms are added over 2 hours whileallowing the batch to exotherm to 127° C. The temperature is thenincreased to 152° C. and the batch is N₂ blown for 1 hour then filtered.The product contains 45% mineral oil, 0.77% N and has total basenumber=15.

EXAMPLE 4

The procedure of Example 3 is repeated replacing the product of Example1 with an equal weight of the product of Example 2. The product contains45% mineral oil, Total base no.=15, total acid no=5.

Other Additives

The compositions of this invention may contain minor amounts of othercomponents. The use of such additives is optional and the presencethereof in the compositions of this invention will depend on theparticular use and level of performance required. The compositions maycomprise metal salts, preferably a zinc salt, of a dithiophosphoricacid. Zinc salts of dithiophosphoric acids are often referred to as zincdithiophosphates, zinc O,O-dihydrocarbyl dithiophosphates, and othercommonly used names. They are sometimes referred to by the abbreviationZDP. One or more zinc salts of dithiophosphoric acids may be present ina minor amount to provide additional extreme pressure, anti-wear andanti-oxidancy performance.

In addition to metal salts of dithiophosphoric acids discussedhereinabove, other additives that may optionally be used in thelubricating oils of this invention include, for example, detergents,auxiliary dispersants, viscosity improvers, oxidation inhibiting agents,metal passivating agents, pour point depressing agents, extreme pressureagents, anti-wear agents, color stabilizers and anti-foam agents.

Phenolic compounds and aromatic amines are useful oxidation inhibitors.Preferred are hindered phenolic compounds, for example, 2,6-ditertiarybutyl phenol and secondary aromatic amine compounds, for exampleN,N-di(alkylphenyl)amines.

Extreme pressure agents and corrosion and oxidation inhibiting agentswhich may be included in the compositions of the invention areexemplified by chlorinated aliphatic hydrocarbons, organic sulfides andpolysulfides, phosphorus esters including dihydrocarbon andtrihydrocarbon phosphites and molybdenum compounds.

Viscosity improvers (also sometimes referred to as viscosity indeximprovers) may be included in the compositions of this invention.Viscosity improvers are usually polymers, including polyisobutenes,polymethacrylic acid esters, diene polymers, polyalkylstyrenes,alkenylarene-conjugated diene copolymers and polyolefins.Multifunctional viscosity improvers, which have dispersant and/orantioxidancy properties are known and may optionally be used. Suchproducts are described in numerous publications.

Pour point depressants are a particularly useful type of additive oftenincluded in the lubricating oils described herein. See for example, page8 of “Lubricant Additives” by C. V. Smalheer and R. Kennedy Smith(Lezius-Hiles Company Publisher, Cleveland, Ohio, 1967). Pour pointdepressants useful for the purpose of this invention, techniques fortheir preparation and their use are described in U.S. Pat. Nos.2,387,501; 2,015,748; 2,655,479; 1,815,022; 2,191,498; 2,666,748;2,721,877; 2,721,878; and 3,250,715 which are expressly incorporated byreference for their relevant disclosures. Examples of pour pointdepressants are polyacrylates, alkylated naphthalenes, styrene/alkylmaleate and fumarate—and maleate ester/vinyl acetate copolymers.

Anti-foam agents used to reduce or prevent the formation of stable foaminclude silicones or organic polymers. Examples of these and additionalanti-foam compositions are described in “Foam Control Agents”, by HenryT. Kerner (Noyes Data Corporation, 1976), pages 125-162.

Detergents and auxiliary dispersants may be of the ash-producing orashless type. The ash-producing detergents are exemplified by oilsoluble neutral and basic salts, wherein “basic salt” is used todesignate metal salts wherein the metal is present in stoichiometricallylarger amounts than the organic acid radical, of alkali or alkalineearth metals with sulfonic acids, carboxylic acids, phenols or organicphosphorus acids characterized by at least one directcarbon-to-phosphorus linkage.

Basic salts and techniques for preparing and using them are well knownto those skilled in the art and need not be discussed in detail here.The extent of overbasing resulting in a basic salt is indicated by theterm metal ratio (MR) which indicates the number of equivalents of baseper equivalent of acid.

Auxiliary ashless detergents and dispersants may be used. These areso-called despite the fact that, depending on its constitution, thedetergent or dispersant may upon combustion yield a nonvolatile residuesuch as boric oxide or phosphorus pentoxide; however, it does notordinarily contain metal and therefore does not yield a metal-containingash on combustion. Many types are known in the art, and any of them aresuitable for use in the lubricants of this invention. The following areillustrative:

(1) Reaction products of carboxylic acids (or derivatives thereof)containing at least 34 and preferably at least 54 carbon atoms withnitrogen containing compounds such as amine, organic hydroxy compoundssuch as phenols and alcohols, and/or basic inorganic materials. Examplesof these “carboxylic dispersants” are described in British Patent number1,306,529 and in many U.S. patents including the following:

3,163,603 3,184,474 3,215,707 3,219,666 3,271,310 3,272,746 3,281,3573,306,908 3,311,558 3,316,177 3,340,281 3,341,542 3,346,493 3,351,5523,381,022 3,399,141 3,415,750 3,433,744 3,444,170 3,448,048 3,448,0493,451,933 3,454,607 3,467,668 3,501,405 3,522,179 3,541,012 3,541,6783,542,680 3,567,637 3,574,101 3,576,743 3,630,904 3,632,510 3,632,5113,697,428 3,725,441 4,194,886 4,234,435 4,491,527 5,696,060 RE 26,433

(2) Reaction products of relatively high molecular weight aliphatic oralicyclic halides with amines, preferably polyalkylene polyamines. Thesemay be characterized as “amine dispersants” and examples thereof aredescribed, for example, in the following U.S. patents:

3,275,554 3,438,757 3,454,555 3,565,804

(3) Reaction products of alkyl phenols in which the alkyl groupscontains at least 30 carbon atoms with aldehydes (especiallyformaldehyde) and amines (especially polyalkylene polyamines), which maybe characterized as “Mannich dispersants”. The materials described inthe following U.S. patents are illustrative:

3,413,347 3,697,574 3,725,277 3,725,480 3,726,882

(4) Products obtained by post-treating the carboxylic amine or Mannichdispersants with such reagents are urea, thiourea, carbon disulfide,aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinicanhydrides, nitrites, epoxides, boron compounds, phosphorus compounds orthe like. Exemplary materials of this kind are described in thefollowing U.S. patents:

3,036,003 3,087,936 3,200,107 3,216,936 3,254,025 3,256,185 3,278,5503,280,234 3,281,428 3,282,955 3,312,619 3,366,569 3,367,943 3,373,1113,403,102 3,442,808 3,455,831 3,455,832 3,493,520 3,502,677 3,513,0933,533,945 3,539,633 3,573,010 3,579,450 3,591,598 3,600,372 3,639,2423,649,229 3,649,659 3,658,836 3,697,574 3,702,757 3,703,536 3,704,3083,708,522 4,234,435

(5) Interpolymers of oil-solubilizing monomers such as decylmethacrylate, vinyl decyl ether and high molecular weight olefins with.monomers containing polar substituents, e.g., aminoalkyl acrylates ormethacrylates, acrylamides and poly-(oxyethylene)-substituted acrylates.These may be characterized as “polymeric dispersants” and examplesthereof are disclosed in the following U.S. patents:

3,329,658 3,449,250 3,519,565 3,666,730 3,687,849 3,702,300The above-noted patents are incorporated by reference herein for theirdisclosures of ashless dispersants.

The above-illustrated additives may each be present in lubricatingcompositions at a concentration of as little as 0.001% by weight usually0.01% to 20% by weight, more often 1% to 12% by weight.

Lubricating Oil Compositions

The lubricating compositions and methods of this invention employ an oilof lubricating viscosity, including natural or synthetic lubricatingoils and mixtures thereof. Mixture of mineral oil and synthetic oils,particularly polyalphaolefin oils and polyester oils, are often used.

Natural oils include animal oils and vegetable oils (e.g. castor oil,lard oil and other vegetable acid esters) as well as mineral lubricatingoils such as liquid petroleum oils and solvent-treated or acid treatedmineral lubricating oils of the paraffinic, naphthenic or mixedparaffinic-naphthenic types.

Hydrorefined, including hydrotreated, hydrocracked and hydroisomerizedoils are included within the scope of useful oils of lubricatingviscosity. These oils are usually substantially saturated being at least90% saturated and often contain no readily discernable unsaturation.These are commercially available from a number of suppliers. Examplesinclude hydroisomerized oils supplied by Neste OY, Finland under thetradename NEXBASE®. Hydrotreated naphthenic oils are also well known.

Oils of lubricating viscosity derived from coal or shale are alsouseful. Synthetic lubricating oils include hydrocarbon oils andhalosubstituted hydrocarbon oils such as polymerized andinterpolymerized olefins and mixtures thereof, alkylbenzenes,polyphenyl, (e.g., biphenyls, terphenyls, and alkylated polyphenyls),alkylated diphenyl ethers and alkylated diphenyl sulfides and theirderivatives, and analogs and homologues thereof.

Polymerized and interpolymerized olefins constitute an especiallypreferred group of synthetic oils. Examples are polyoctenes andpolydecenes. These typically have viscosities at 100° C. of 4 to 10mm²/s (centistokes), more often 40 to 8, often to 6 mm²/s. In oneembodiment, the oil of lubricating viscosity comprises at least 20%, andpreferably at least 25 percent or 30% or greater by weight of apolyolefin basestock.

Alkylene oxide polymers and interpolymers and derivatives thereof, andthose where terminal hydroxyl groups have been modified by methods suchas esterification or etherification, constitute other classes of knownsynthetic lubricating oils that can be used.

Another suitable class of synthetic lubricating oils that can be usedcomprises the esters of dicarboxylic acids and those made from C₅ to C₁₂monocarboxylic acids and polyols or polyol ethers.

Other synthetic lubricating oils include liquid esters ofphosphorus-containing acids, polymeric tetrahydrofurans, andsilicon-based oils such as the polyalkyl-, polyaryl-, polyalkoxy-, orpolyaryloxy-siloxane oils and silicate oils.

Unrefined, refined and rerefined oils, either natural or synthetic (aswell as mixtures of two or more of any of these) of the type disclosedhereinabove can used in the compositions of the present invention.Unrefined oils are those obtained directly from a natural or syntheticsource without further purification treatment. Refined oils are similarto the unrefined oils except they have been further treated in one ormore purification steps to improve one or more properties. Rerefinedoils are obtained by processes similar to those used to obtain refinedoils applied to refined oils which have been already used in service.Such rerefined oils often are additionally processed by techniquesdirected to removal of spent additives and oil breakdown products.

In one embodiment, preferred oils of lubricating viscosity comprise APIGroup III oils. These contain ≦0.03% sulfur, ≧90% saturates andviscosity index ≧120. Usually, the basestock comprises less than 50% byweight of Group III basestocks.

Oils of lubricating viscosity used in this invention may containmixtures of two or more of the foregoing oils. In a preferredembodiment, mixtures of hydrorefined basestocks and syntheticbasestocks, particularly polyolefins and more particularly polyolefinshaving a viscosity at 100° C. of 4 to 8 mm²/s (centistokes).Particularly preferred are mixtures of Group III oils and polyolefinsdescribed hereinabove. In one preferred embodiment, the Group III oil isa hydroisomerized basestock. In another preferred embodiment, themixture comprises more than 30% by weight of a polyolefin oil.

Specific examples of the above-described oils of lubricating viscosityare given in Chamberlin III, U.S. Pat. No. 4,326,972 and European PatentPublication 107,282, both of which are hereby incorporated by referencefor relevant disclosures contained therein.

Sequeria, Jr., in Lubricant Base Oil and Wax Processing, Marcel Deker,Inc., New York, N.Y., USA (1994) discusses lubricant oils and processesfor preparing them. Hydrogen refining proce3sses are specificallydescribed at pages 119-152 thereof.

A basic, brief description of lubricant base oils appears in an articleby D. V. Brock, “Lubrication Engineering”, Volume 43, pages 184-5,March, 1987, which article is expressly incorporated by reference forrelevant disclosures contained therein.

Lubricating oil compositions of this invention comprise a major amountof an oil of lubricating viscosity and a minor amount of the acylatedamine of this invention.

In one preferred embodiment, the lubricating oil composition furthercomprises a metal overbased detergent, preferably a sulfonate detergent,more preferably, a calcium overbased alkyl benzene sulfonic acid.

The lubricating oil composition typically comprises at least 1.2 or 2.5%by weight of the acylated amine and from about 0.25 or 0.5% to about 5%by weight of the metal overbased detergent (each on an active chemicalbasis) and has total base number of 3 to 15 wherein the acylated aminecontributes at least 10% of the total base number.

Additive Concentrates

The composition of this invention may be present as a component of anadditive concentrate. Additive concentrates comprise the compositions ofthis invention, optionally together with other performance improvingadditives in concentrated form, usually in the presence of asubstantially inert, normally liquid, organic diluent. A wide variety ofdiluents such as hydrocarbon solvents and oils are useful diluents. Moreoften, the diluent is an oil of lubricating viscosity.

A typical additive concentrate comprises 20% to 80% by weight of anacylated amine of this invention and 80% to 20% by weight of a normallyliquid organic diluent. Other components may also be present in additiveconcentrates such as the other additives described hereinabove.

The following Examples illustrate lubricating oil compositions of thisinvention. All parts and percentages are by weight and unless specifiedotherwise, are on an oil or diluent-free basis.

EXAMPLE A

An additive concentrate is prepared by combining and mixing at anelevated temperature, 49.28 parts of the acylated amine of Example 4,8.62 parts of a zinc salt of a mixed isopropyl-methyl amyldithiophosphate, 6.76 parts dialkyl diphenylamine, 1.93 parts sulfurizedbutadiene-butyl acrylate adduct, 1.93 partsisooctyl-3,5-di-t-butyl-4-hydroxy hydrocinnamate (Ciba-Geigy, IRGANOX®L-135), 1.93 parts glycerol monooleate, 4.51 parts calcium overbased (MR11) alkyl benzene sulfonic acid, 5.58 parts calcium overbased (MR 20)alkyl benzene sulfonic acid, 0.09 parts of a siloxane based antifoamagent and sufficient mineral oil to prepare 100 parts of additiveconcentrate. A lubricating oil composition is prepared by mixing, at anelevated temperature, 10.35 parts of the additive concentrate andsufficient oil of lubricating viscosity (Texaco) to prepare 100 parts oflubricant.

EXAMPLE B

An additive concentrate is prepared by combining and mixing at anelevated temperature, 58.94 parts of an acylated amine prepared as inExample 4, 5.90 parts of a zinc salt of a mixed isopropyl-methyl amyldithiophosphate, 3.31 parts dialkyl diphenylamine, 3.31 parts of at-butylated phenol, 0.1 part of oleylamide, 6.06 parts calcium overbased(MR 3.5) sulfurized alkyl phenol, 5.38 parts calcium overbased (MR11)alkyl benzene sulfonic acid, 3.31 parts calcium overbased (MR 1.2) alkylbenzene sulfonic acid, 0.1 parts of a siloxane based antifoam agent andsufficient mineral oil to prepare 100 parts of additive concentrate. Alubricating oil composition is prepared by mixing, at an elevatedtemperature, 15.1 parts of the additive concentrate and sufficient oilof lubricating viscosity (31.8% 4 mm²/s (cSt) polyalphaolefin (Chevron)and 68.2% hydroisomerized base oil (5 mm²/s (cSt)/135 N, NEXBASE® 3050))to prepare 100 parts of lubricant.

It is known that some of the materials described above may interact inthe final formulation, so that the components of the final formulationmay be different from those that are initially added. For instance,metal ions (of, e.g., a detergent) can migrate to other acidic sites ofother molecules. The products formed thereby, including the productsformed upon employing the composition of the present invention in itsintended use, may not susceptible of easy description. Nevertheless, allsuch modifications and reaction products are included within the scopeof the present invention; the present invention encompasses thecomposition prepared by admixing the components described above.

Each of the documents referred to above is incorporated herein byreference. Except in the examples, or where otherwise explicitlyindicated, all numerical quantities in this description specifyingamounts of materials, reaction conditions, molecular weights, number ofcarbon atoms, and the like, are to be understood as modified by the word“about.” Unless otherwise indicated, each chemical or compositionreferred to herein should be interpreted as being a commercial gradematerial which may contain the isomers, by-products, derivatives, andother such materials which are normally understood to be present in thecommercial grade. However, the amount of each chemical component ispresented exclusive of any solvent or diluent oil which may becustomarily present in the commercial material, unless otherwiseindicated. It is to be understood that the upper and lower amount,range, and ratio limits set forth herein may be independently combined.As used herein, the expression “consisting essentially of” permits theinclusion of substances which do not materially affect the basic andnovel characteristics of the composition under consideration.

While the invention has been explained in relation to its preferredembodiments, it is to be understood that various modifications thereofwill become apparent to those skilled in the art upon reading thespecification. Therefore, it is to be understood that the inventiondisclosed herein is intended to cover such modifications that fallwithin the scope of the appended claims.

1. A composition of matter comprising an amine acylated with ahydrocarbyl group substituted carboxylic acylating agent containing anaverage of about 1.3 to about 1.6 groups derived from α,β-unsaturatedcarboxylic compounds per equivalent of the hydrocarbyl group, whereinthe equivalent weight of the hydrocarbyl is defined as its M _(n,)determined by GPC, which is about 1500 to about 3000, the aminecomprises polyamine bottoms, and said acylated amine has total basenumber (TBN) of about 17 to about 35 on a neat chemical basis, whereinsaid hydrocarbyl group substituted carboxylic acylating agent (i) isprepared by direct thermal alkylation of an α,β-unsaturated carboxyliccompound with a polyolefin, or (ii) is prepared by a process comprisingforming a mixture of a polyolefin having a total of tetra- and tri-substituted unsaturated end groups up to 90 mole % based on moles ofpolyolefin and a halogen selected from the group consisting of chlorineand bromine, with an α,β-unsaturated carboxylic compound.
 2. Thecomposition of claim 1 wherein the hydrocarbyl group substituentcomprises a polyisobutylene group.
 3. The composition of claim 1 whereinthe carboxylic groups comprise at least one member of the groupconsisting of succinic acid, propionic acid, and reactive equivalentsthereof.
 4. The composition of claim 1 wherein the hydrocarbyl group hasa M _(n) of about 1700 to about
 3000. 5. The composition of claim 1having on a neat chemical basis, total base number of about 20 to about30.
 6. The composition of claim 1 having on a neat chemical basis,chlorine content of up to about 0.6%.
 7. The composition of claim 1further comprising about 30 to about 70 parts of a diluent, per 100parts by weight of the composition.
 8. The composition of claim 7wherein the diluent comprises a mineral oil.
 9. The composition of claim1 wherein the hydrocarbon group substituted acylating agent is preparedby a process comprising forming a mixture of a polyolefin having a totalof tetra- and tri- substituted unsaturated end groups up to about 90mole % based on moles of polyolefin and a halogen selected from thegroup consisting of chlorine and bromine, wherein said halogen ispresent in said mixture on a molar basis up to an amount equal to themoles of tetra- and tri- substituted end groups and adding to saidmixture from about 1.5 to about 2.5 moles per equivalent of polyolefinof an α,β-unsaturated carboxylic compound, sequentially orsimultaneously with addition of said halogen, reacting said mixture atfrom about 170° C. to about 220° C. to effect reaction of the polyolefinand α,β-unsaturated carboxylic compound, reducing the temperature toless than about 200° C. and adding thereto additional halogen on a molarbasis up to an amount equal to the moles of tetra- and tri- substitutedend groups, then reacting the mixture to reduce unreacted α,β-unsaturated carboxylic compound to less than about
 3. 10. Thecomposition of claim 9 wherein said polyolefin comprisespolyiso-butylene.
 11. An additive concentrate comprising about 20% toabout 80% by weight of the acylated amine of claim 1 and about 80% toabout 20% by weight of a normally liquid organic diluent.
 12. Alubricating oil composition comprising a major amount of an oil oflubricating viscosity and a minor amount of the acylated amine ofclaim
 1. 13. The lubricating oil composition of claim 12 furthercomprising a metal overbased sulfonate detergent.
 14. The composition ofclaim 13 wherein the metal overbased detergent is a calcium overbasedalkyl benzene sulfonic acid.
 15. The lubricating oil composition ofclaim 13 comprising at least about 1.2% by weight of the acylated amineand from about 0.25% to about 5% by weight of the metal overbaseddetergent.
 16. The lubricating oil composition of claim 13 having totalbase number of about 3 to about 15 wherein the acylated aminecontributes at least about 10% of the total base number.
 17. Thelubricating oil composition of claim 12 wherein the oil of lubricatingviscosity comprises more than 20% by weight of a polyolefin basestock.18. The lubricating oil composition of claim 17 wherein the oil oflubricating viscosity comprises a mixture of (a) polyolefin basestockshaving a viscosity at 100° C. of about 4 to about 8 mm2/s (centistokes)and (b) an API Group III basestock.
 19. A composition of mattercomprising an amine acylated with a hydrocarbyl group substitutedcarboxylic acylating agent containing an average of about 1.3 to about1.6 groups derived from α,β-unsaturated carboxylic compounds perequivalent of the hydrocarbyl group, wherein the equivalent weight ofthe hydrocarbyl is defined as its M _(n), determined by GPC, which isabout 1500 to about 3000, the amine comprises polyamine bottoms, andsaid acylated amine has total base number (TBN) of about 17 to about 35on a neat chemical basis, wherein said hydrocarbyl group substitutedcarboxylic acylating agent is prepared by direct thermal alkylation ofan α,β-unsaturated carboxylic compound with a polyolefin.
 20. Thecomposition of claim 19 wherein at least about 30% of the terminalgroups are vinylidene groups.